https://github.com/hashcloak/noir-fixed-point
Fixed point arithmetic library in Noir
https://github.com/hashcloak/noir-fixed-point
Last synced: 2 months ago
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Fixed point arithmetic library in Noir
- Host: GitHub
- URL: https://github.com/hashcloak/noir-fixed-point
- Owner: hashcloak
- License: apache-2.0
- Created: 2025-01-08T21:02:25.000Z (4 months ago)
- Default Branch: main
- Last Pushed: 2025-02-07T17:21:48.000Z (3 months ago)
- Last Synced: 2025-02-07T18:19:59.492Z (3 months ago)
- Language: Noir
- Size: 33.2 KB
- Stars: 0
- Watchers: 1
- Forks: 0
- Open Issues: 1
-
Metadata Files:
- Readme: README.md
- License: LICENSE
Awesome Lists containing this project
- awesome-noir - Fixed Point Library for scale 2^-16 - an optimized fixed point arithmetic library designed for scale 2^-16. (Libraries / Data Types)
README
# Fixed-Point Arithmetic Library
This is an optimized fixed point arithmetic library designed for scale 2^-16. It supports signed fixed-point numbers with a specific scale of 2^-16 and provides efficient implementations of standard arithmetic operations such as addition, subtraction, and multiplication.
## Usage
To create a fixed-point number, divide the original value by 2^16 and store the resulting integer:
```rust
let value = Quantized::new(65536); // Represents 65536 / 2^16 = 1.0
let small_value = Quantized::new(32768); // Represents 32768 / 2^16 = 0.5
let large_value = Quantized::new(131072); // Represents 131072 / 2^16 = 2.0
```
Arithmetic operations. Note that for multiplication we always scale down the value so the result has the same scale as before.
```rust
let a = Quantized::new(98304); // Represents 1.5
let b = Quantized::new(147456); // Represents 2.25
let add = a + b; // (98304 + 147456) / 2^16 = 3.75
let sub = a - b; // (98304 - 147456) / 2^16 = -0.75
let mul = a * b; // (98304 * 147456) / 2^(16 + 16) = 3.375
```
### Check Negativity
You can check whether a fixed-point value is negative:
```rust
let negative_value = Quantized::new(-32768); // Represents -0.5
let is_negative = is_negative(negative_value.x); // Returns 1 (true)
let positive_value = Quantized::new(65536); // Represents 1.0
let is_positive_negative = is_negative(positive_value.x); // Returns 0 (false)
```
## Testing
Run tests with:
```bash
cargo test
```
## Benchmarks
Gatecounts:
Addition & subtraction: 17.
Multiplication: 2922
Division: 3285.
Ordering: 2789.
Rerun benchmarks in folder `benchmarks`.
- Nargo `1.0.0-beta.0`
- bb `0.63.0`